Telephone dial illumination



J 1933' R. FOSTER ET AL TELEPHONE DIAL ILLUMINATION Filed July 9, 1932 Inventor fleu ban T0632 1" M J'ynzaazalflizldazf Patented Jan. 3, 1933 UNITED STATES PATENT mm; 7

REUBEN FOSTER AND SIGMUND K. WALDORF, OF BALTIMORE, MARYLAND; SAID WALDORE ASSIGNOR TO SAID FOSTE v v -TELEPHONE DIAL ILLUMINATION Application filed my 9,

The resent invention appertains to new and use 111 improvements in the telephonic art and more particularly to telephones of the dial type. The invention aims to provlde means for adequately illuminating the dial of a telephone so that its characters will be clearly visible to the user thereof.

Another important object of the invention is to provide illuminating means for telephone dials wherein current is supplied thereto by interconnection with the telephone system.

Another important object of the invent on is to provide in combination, a telephone dial, electrical illuminating means for the d al and a telephone system with the llluminating means installed therein, whereby it will automatically become energized upon the establishment of the system in service.

Still another important object of the invention is to provide a telephone dial and illuminating means therefor, in combination with a telephone system in which the illuminating means is interposed, and in further comblnation with means for automatically cuttin out the illuminating means from the telep one circuit in the event the samebecomes defective.

These and various other important objects and advantages of the invention will become apparentto'the reader of the following specification.

In the drawing: Figure 1 represents a side elevational view of a conventional telephone stand and dial showing in section the illuminating means.

Figure 2 represents a dia ammatic view showing a conventional telep one system and the novel illuminating means and safety circuit connected therewith.

Referring to the drawing wherein like numerals designate like parts, it can be seen in Figure 1, that numeral 5 generally refers to the tele hone piece which involves the base 6 upon which the dial 7 is mounted, the receiver hook 8, and the transmitter generally referred to by numeral 9, the receiver 10 being shown in the diagrammatic view Figure 2.

In the telephone system generally referred to by numeral 11 in Figure 2, numeral 12 denotes the usual ringing bell, while numeral 1932. Serial 170,621,716.

invention, numeral 16 represents the lead extending to a contact at the receiver hook 8. In this lead 16 is installed the lamp 17 which as shown in Figure 1 is placed in a barrel 18 and has a bulls eye or lens 19 for s reading the light over the dial 7. This barre or casing 18 is suitablysecured by screws or other means 20 to the telephone stand 5. p

It can now be seen, that immediately upon releasing the book 8, the contacts 21 will be engaged by the hook. Current will'now flow in the lead 16 through the lamp 17 thus energizing the lamp and illuminating the dial 7. This lamp 17 remains energized so long as thetele hone system is in service, and immediate y upon placement of the receiver 10 upon the hook 8, the telephone system being disrgpted, the lamp 17 also becomes de-enerze' I Therefore, the function of the lamp 17 is entirely automatic. Furthermorefthe lamp 17 in no way interferes with the service of the telephone system in the event the lamp becomes defective because of an additional provision in the auxiliary circuit 22. In the circuit 22 is provided the magnetic coil 23 which when energized moves the armature 24 which in turn releases and closes the switch 25, permitting current to flow by way of the circuit 221instead of through the lamp 17. The coil 23 is energized upon failure of the lamp 17 and consequent interruption of the circuit at lamp 17, by an increase in current flowing in coil 23 under these circumstances;

As the magnitude of the current flowing in a subscribers line varies with different insta1- lations, the resistance 26 placed between the conductors 16 and 22 is adjusted to by-pass current in excess of the value safe for the lamp 17 to carry. The resistance 26 can be omitted if the current flowing in the subscribers line is not excessive for the lamp.

It can thus be seen, that in the event the -lamp 17 burns out, a larger current will flow in the coil 23 to attract the armature 24 which results in the closing of the switch 25 and the establishment of a current path around the lam 17 by way of the circuit 22.

hile the foregoing specification sets forth the invention in specific terms, it is to be understood that numerous changes in the shape, size and materials may be resorted to without departing from the spirit and scope of the invention as claimed hereinafter.

Having thus described our invention, what we claim as new is:

1. In combination, a telephone system including a switching devlce, illuminating means for the switching device, said means being in the system, and controlled incident thereto, an auxiliary circuit shunting the said illuminating means, and a device controlled by the telephone circuit to establish the auxiliary circuit for passing current around the illuminating means when the latter is defective.

2. In combination, a telephone switching system including a switching device, illuminating means for the switching device, said means beng in the system and controlled incident thereto, an auxiliary circuit shunting the said illuminating means, a device controlled by the telephone circuit to establish the circuit for passing current around the illuminatmg means when the latter is defective, and a resistance across the said circuit for bypassing current in excess of the value safe for the illuminating means to carry.

3. In combination, a telephone circuit, a telephone subscribers switching device, illuminating means for the switching device,

said means being connected with the circuit.

to obtain energy therefrom, and auxiliary means for shunting the energy around the illuminating means in the event the said illaminating means becomes defective.

4. In combination, a telephone circuit, a telephone subscribers switching device, illuminating means for the switching device, said means being connected with and controlled by said telephone circuit,-and automatic means for shunting the current supply of the telephone circuit around the illuminating means in the event the illuminating means becomes defective.

In testimony whereof we aflix our signatures.

REUBEN FOSTER. SIGMUND K. WALDORF. 

